Aesthetics (encodings)

PH345: Winter 2025

Phil Boonstra

Farbtafel, Paul Klee (1930)

Which color appears most often?

https://www.demilked.com/tidying-up-art-ursus-wehrli/

Tidied up Farbtafel, Ursus Wehrli (2003)

Which color appears most often?

https://www.demilked.com/tidying-up-art-ursus-wehrli/

Mapping data to aesthetics

Aesthetics or encodings are ways that we map data to visual properties of the plot and include position, color, length, shape, area, volume

Choice of aesthetics helps or hinders your audience’s understanding of what the data are showing

Example: five proportions

One proportion for each of five groups (A-E)

For each of 9 plots, guess group B’s numerical proportion and rank. Enter your guesses on this google form:

Plot 1

Plot 2

Plot 3

Plot 4

Plot 5

Plot 6

Plot 7

Plot 8

Plot 9

True values

Plot True value B True rank B
1 0.160 3
2 0.205 3
3 0.333 5
4 0.365 5
5 0.254 4
6 0.161 2
7 0.283 4
8 0.034 1
9 0.098 2

Types of data

  • Quantitative: numbers that measure units, e.g. years, kg, etc. Differences between numbers have meaning
  • Ordinal: numbers or categories that have natural order, e.g. Likert scales, tumor stage. Distances between numbers do not have consistent meaning (‘Almost always’ - ‘Sometimes’ = ?)
  • Nominal: Categories that have no inherent order, e.g. US states